Effective tribofilms are desirable to protect mechanical systems. In the present research, we investigated the formation of a tribofilm through the use of α-ZrP (Zr(HPO4)2 ̈H2O) as an additive. Experiments were conducted on a base oil where 0.2 wt% of the additive was used. Experimental results showed a 50% reduction in friction and a 30% reduction in wear when compared to the base oil containin...

The dielectric properties of electrochemically grown zirconium oxide films by anodisation of zirconium in 1.0 mol dm-3 phosphoric acid solution were investigated in a 3 to 30 V potential range with a view to inducing surface modifications for eventual use in biomedical and electronic applications. The oxide films grown at different potentials were characterised by Atomic Force Microscopy, X-ray...

objectives: fracture strength is an important factor influencing the clinical long-term success of implant-supported prostheses especially in high stress situations like excessive crown height space (chs). the purpose of this study was to compare the fracture strength of implant-supported fixed partial dentures (fpds) with excessive crown height, fabricated from three different materials. mater...

the interest of dental research in metal-free restorations has been rising in the last 20 years following the introduction of innovative all-ceramic materials in the daily practice. in particular, high-strength ceramics and related cad/cam techniques have widely increased the clinical indications of metal-free restorations, showing more favorable mechanical characteristics compared to the early...

objectives : the purpose of this in vitro study was to compare the marginal adaptation and fracture resistance of a zirconia-based all-ceramic restoration with two preparation designs. materials and methods: twenty-four mandibular premolars were randomly divided into two groups (n=12); the conventional group received a peripheral shoulder preparation and the modified group received a buccal sho...

in this study, isophthalic acid-zirconium(iv) nanocomposite has been prepared from zirconyl nitrate pentahydrate and potassium iodide, with isophthalic acid, (c8h6o4=benzene-1,3-dicarboxylic acid) as a ligand, via sonochemical method in ethylene glycol and methanol as solvents. the crystalline tetragonal zro2 has been produced by thermal decomposition of isophthalic acid-zirconium(iv) nanocompo...

It is well known that the structure of ZrO2 powder synthesized by low temperature calcination of hydrous zirconia is strongly affected by the nature and properties of precursors. In the present paper, we combined a precipitation/restructuring approach (bottom-up/top-down methodology) to produce zirconium hydroxide nanoparticles that transform into stable nanophasic tetragonal zirconia by low te...

PURPOSE The purpose of this in vitro study is to examine the effects of a nano-structured alumina coating on the adhesion between resin cements and zirconia ceramics using a four-point bending test. MATERIALS AND METHODS 100 pairs of zirconium bar specimens were prepared with dimensions of 25 mm × 2 mm × 5 mm and cementation surfaces of 5 mm × 2 mm. The samples were divided into 5 groups of 2...